Permitted Lien shall mean: (i) any Lien for Taxes which are either not assessed or, if assessed, are not yet due and payable or are being contested in good faith by appropriate proceedings so long as such proceedings shall not involve any material risk of the sale, forfeiture or loss of the Aircraft; or (ii) any undetermined or inchoate Lien of a repairer, carrier, hangarkeeper, material supplier or other similar Lien arising in the ordinary course of business in respect of obligations which are not overdue or which have been adequately bonded or are being contested in good faith by appropriate proceedings; provided that (in the case of both (i) and (ii)) such proceedings, or the continued existence of such Lien, do not involve any material risk of the sale, forfeiture or loss of the Aircraft; or (iii) the respective rights of the parties to the Operative Agreements as set forth therein, and any Liens expressly permitted thereby including Liens granted by the Lessor